A383201 Number of positive integers with n digits in which adjacent digits differ by at most 6.

9, 81, 724, 6472, 57851, 517112, 4622299, 41317257, 369321783, 3301249634, 29508817638, 263769909867, 2357755102376, 21075220921085, 188384678470177, 1683910560899833, 15051939468415328, 134544486519385896, 1202650255852445247, 10750107085908359068

Offset

1,1

Links

Table of n, a(n) for n=1..20.

Index entries for linear recurrences with constant coefficients, signature (8,9,-5,-4).

Formula

G.f.: -x*(4*x^3+5*x^2-9*x-9)/(4*x^4+5*x^3-9*x^2-8*x+1). - Alois P. Heinz, Apr 26 2025

Crossrefs

Cf. A235163, A383197, A383198, A383199, A383200, A383202.

Sequence in context: A382139 A125910 A171283 * A174108 A254435 A267790

Adjacent sequences: A383198 A383199 A383200 * A383202 A383203 A383204

Keyword

nonn,base,easy

Author

Edwin Hermann, Apr 19 2025

Extensions

a(11)-a(20) from Alois P. Heinz, Apr 26 2025

Status

approved